一浴法および二浴法によって作製されたCu/Niナノオーダー多層めっき膜の耐摩耗性

Abstract

An abrasion wear tester was used to ascertain the difference between the wear resistances of Cu/Ni multilayer films that were prepared electrochemically using single or dual baths. The formation of oxide layers on the deposited layers and the containment of phosphorus in the Ni layers improved the films' wear resistance. For conditions in which phosphorus was contained and surface oxide layers were formed, the film prepared using a dual bath exhibited slightly higher wear resistance than the film prepared using a single bath. The difference in the wear resistances was regarded as caused by the difference in the degree of the film surfaces' exposure to air because the film was exposed directly to air during transfer between the two baths in the dual-bath method. Therefore, for the single-bath method, the exposure of Ni layers to air after electrodeposition of each layer produced higher wear resistance of the film. Detailed analysis of the oxidation state of the metal and the surface morphology of the films using an X-ray photoelectron spectroscope, a scanning electron microscope, and an atomic force microscope revealed that the smooth Ni oxide layer formed on the Ni layers contributes to improved wear resistance of the films.